Fuel economy and emissions performance of an automobile is an important characteristic. A higher fuel economy and lower emissions rating may make a vehicle more attractive to potential buyers and may help an automotive manufacturer meet fuel economy and emissions standards imposed by local governments. One method of reducing fuel consumption and decreasing vehicle emissions is capturing kinetic energy generated by a moving vehicle. Capturing kinetic energy dissipated when friction brakes are applied is well known. However, these methods often involve complex and expensive components. Kinetic energy may also be present and lost within an automatic transmission. Automatic transmissions may utilize pressurized hydraulic fluid to power the various hydraulic components within the transmission.